Microassay of inorganic sulfate in biological fluids by controlled flow anion chromatography

The application of controlled flow anion chromatography to the assay of inorganic sulfate in biological fluids is described. The sulfate anion is separated from other anions by ion-exchange chromatography and quantitated conductimetrically. Coefficient of variance is 3.4%, about half that for the barium precipitation assay. Interference from heparin in plasma samples and unknown sources in tissue extract analysis is avoided. Sulfate levels in plasma are not different from those measured in serum after protein precipitation. Normal levels for sulfate concentration in human plasma, cerebrospinal fluid and hepatic tissue extract are reported.